Contact block and terminal arrangement



Dec. 26, 1961 w. E. ELsNER ETAL CONTACT BLOCK AND TERMINAL ARRANGEMENT MA A "-7.

.m ...l Wlmll A IIL- Filed Dec.

Dec. 26, 1961 W. E. ELSNER ETAL CONTACT BLOCK AND TERMINAL ARRANGEMENTFiled Dec.

2 Sheets-Sheet 2 IN V EN TORS Wa/aem/EF/ze United States Patent Giiice3,015,006 Patented Dec. 26, 1961 3,015,006 CONTACT BLOCK AND TERMINALARRANGEMENT Waldemar E. Elsner, Aurora, and Robert L. McGary,

West Chicago, Ill., assignors 'to Furnas Electric Company, Batavia,Ill., a corporation of Delaware Filed Dec. 16, 1960, Ser. No. 76,337 7Claims. (Cl. 200 83) The invention relates to electric switches and hasreference to electric switches of the pressure type having a togglemember which is moved in response to certain pressure conditions toetect opening and closing of the contacts of the switch.

An object of the invention resides in the provision of a pressureactuated switch having a contact block associated therewith and whichpreferably contains normally closed contacts and normally open contacts.The present switch additionally incorporates a toggle member adapted tomove in response to certain pressure conditions and which is operativeto effect opening and closing of the said contacts.

Another object is to provide a pressure switch of the toggle actuatedtype having normally closed contacts and normally open contacts andwherein the normally closed'contacts are actuated by a push rod whichcon nects the said contacts with the toggle member of the switch,whereas the normally open contacts are actuated by a pull rod alsohaving an operative connection with the toggle member.

Another object of the invention is to provide a switch such as describedwhich will have general utility as regards pressure switch applicationsand uses, since all the contacts of the switch may be of the normallyclosed or of the normally open type, with both of the connecting membersbeing either push or pull rods, respectively.

A further object is to provide a pressure switch having a toggle memberfor actuating the contacts thereof, said switch being relatively simplein structure, although positive and highly eicient in operation.

With these and other objects in view, the invention may consist ofcertain novel features of construction and operation, as will be morefully described and particularly pointed out in the specification,drawings and claims appended thereto.

In the drawings which illustrate an embodiment of the device and whereinlike reference characters are used to designate like parts: A

FIGURE 1 is an elevational view showing the switch of the invention asenclosed within a housing;

FIGURE 2 is a vertical sectional view through the switch device ofFIGURE 1 taken substantially on line 2 2 of said ligure, and whichillustrates in detail the several improvements which have beenincorporated in the switch structure;

FIGURE 3 is a vertical sectional view taken substantially along line 3 3of FIGURE 2;

FIGURE 4 is a vertical sectional view taken substantially along line 4 4of FIGURE 2;

FIGURE 5 is a horizontal sectional view taken substantially along line 55 of FIGURE 3, the same showing the toggle structure and the push andpull rods in operative relation therewith;

FIGURE 6 is a top plan view showing the contact block and terminalarrangement such as may be associated with the toggle type of pressureswitch as disclosed;

FIGURE 7 is a vertical sectional view taken substantially along line 7 7of FIGURE 4 and illustrating the action of the toggle member and pushrod in actuating the normally closed contacts; and

FIGURE 8 is a vertical sectional view taken substantially along line `88 of FIGURE 4 and illustrating the action of the toggle member and pullrod in actuating normally open contacts.

The pressure switch which has been selected for illustrating theinvention includes an adaptor or base portion 10 having a threaded inlet11 for admitting a fluid under pressure, and which is suitably securedby the screws 12 to the supporting ring 13 of the switch structure. Thebottom wall 14 of the housing 15, together with the flexible diaphragm16 are interposed between the parts 10 and 13 so that the switchstructure, housing and adaptor are txedly joined together as a unit. Thebottom wall 14 of the housing has an opening 17 in alignment with theinlet 11 so that the pressure fluid in the inlet is in direct contactwith the undersurface of the diaphragm 16 to flex the same in a mannerdepending on the pressure conditions to which the diaphragm issubjected. The toggle mechanism of the present switch is in turnactuated by the llexing of the diaphragm 16 and as the toggle mechanismis caused to oscillate from one side of a dead center position to theother, the contacts of the switch are respectively actuated.

The supporting ring structure 13 is accordingly lxedly secured to thehousing 15, and said ring structure has associated therewith the frameassembly 20 and the pivot structure comprising the pivots 21 for thelever 22. The frame assembly shown in FIGURES 3 and 4 is substantiallyU-shaped and the same has its bottom wall ixedly secured to thesupporting ring 13. The said frame assembly thus provides the upstandingside walls 23 and 24 which are bent outwardly at their upper ends toform the tlanges 25 and 26. Said anges in turn support the contact blockwhich is designated in its entirety by the numeral 28. The screws 27extend through side extensions formed on the contact block and the saidscrews are threaded into the flanges 25 and 26 for releasably securingthe contact block to the frame assembly 20. The side walls 23 and 24 areeach slotted or notched at 30 as best shown in FIGURE 8, and the pivotends of the lever 22 are located in the notches for pivotally mountingthe lever on the frame assembly 20. The stop portion 31, FIGURE 7, whichis fixed to and extends upwardly from the ring 13 is located at theopposite end of the lower 22, and said stop limits movement of the leverin a downward direction under tension of the coil spring 32.

Said coil spring 32 has encircling relation with the rod 33 which isanchored at its base end in the ring structure 13, and which extendsupwardly from said structure to approximately the top surface of thecontact block 28. The top end of the coil spring 32 is confined by thecap 34 which is threaded on the upper end of the rod 33. The cap can beadjusted on said rod as regards its position vertically so as to varythe compressive force exerted by the spring on the lever 22.

The pivot structure 21 comprises the actuator for the lever 22, sincethe same includes a base 35, FIGURE 2, which provides the pivots 21, thesame being integral therewith. The base 35 is located in contact withthe exible diaphragm 16 on the top side thereof, and thus the pivotstructure will move bodily in a vertical direction as the pressure uidon thediaphragm 16 causes the same to ex. This bodily movement of thepivots 21 will be transmitted to the lever 22, and accordingly saidlevel` will oscillate with respect to the pivot axis 30.

The toggle member 36, having the shape as shown in FIGURE 5, ispivotally mounted at its extremities as at 37 on the frame assembly 20.Whereas the pivot ends 30 for the lever 22 are located at the left edgeof each side wall 23 and 24, the pivot extremities 37 of the togglemember engage in notches on the right edge of the said side walls. Also,it will be observed that whereas the lever 22 is disposed in surroundingrelation with the frame assembly, the toggle member 36 is located withinthe side walls 23 and 24. This locates the movable end of the togglemember adjacent the threaded Screw 38 which is located in plate di),FIGURE 3. The screw is adjustable in a vertical direction to limitupward movement of the said toggle member. When the toggle member iscaused to move downwardly its position is limited by the bottom wall ofthe frame assembly. The toggle structure of the switch is completed bythe coil spring l1 which is retained at its left hand end by the togglemember and at its right hand end by the nose 42 provided by the lever22, FlGURE 5.

The contact block assembly 2S which is ixedly secured to the frameassembly by the screws 27 is preferably formed of a moldable plastic,although other insulating materials may be used. Said block is coredinternally to provide the recesses 43, 44, 45 and 46, and the cavities47 and 48. The recesses are accessible from the top of the block, FIGURE6, for receiving terminal screws to be presently described. The cavitiesare open at the bottom of the block and said cavities contain thecontacts ot1 the switch. The insulating plate 56 is suitably secured tothe bottom surface of the block and said plate closes the cavities,although the said plate is readily removable Jfor convenient access tothe contacts.

Refering again to the particular recesses 43 and 44, it will be seenthat conductors 51 and 52 terminate therein with each conductor beingthreadedly secured to the contact block by the respective terminalscrews 53 and 54. As best shown in FlGURES 2 and 7 the conductors 51 and52 are in the form of metal strips and the same extend vertically of theside walls of the contact block to eventually enter and terminate withinthe cavity 55, FIG- URE 7. ln said cavity the conductors 51 and 52contact with and the same are supported by the insulating plate 50, andthe supported terminal ends of the conductors are each provided withsilver contacts for coaction with silver contacts carried by the contactstrip 56. The strip is yieldingly biased by the coil spring 57 havingencircling relation with portion 5S of the push rod 60. The intermediateportion of the push rod 60 is enlarged for engagement with the contactstrip 56. Thus the strip iS yieldingly biased on one side by the coilspring 57 and is held to the push rod on the opposite side. The push roddepends downwardly through insulating plate 50 for eventual contact withthe toggle member 36.

When the toggle member is below a dead center position as shown inFlGURE 7, the pressure of the fluid for actuating the diaphragm 16 willbe below a preset limit. Accordingly the push rod will be located asshown in said gure. rlhe push rod is under the compressive force exertedby coil spring 57 to thus maintain the contact strip S6 in contact withthe conductors 51 and 52. This structure constitutes the normally closedcontacts of the switch.

Recesses 45 and 46 contain conductors 61 and 6?. and which terminatewithin said recesses, the said terminal ends being held to theinsulating contact block by the terminal screws 63 and 64, respectively.The conductors 61 and -62 also extend downwardly on one side of thecontact block to eventually enter at the top of the cavity 65, lilGURE8, where the conductors terminate. Silver contacts are also provided foreach terminal end within the cavity 65 and similar contacts are locatedon the contact strip 66. The said strip is yieldingly biased in anupward direction by the coil spring 67 which is located on the pull rod68, being confined between the strip 66 and the insulating wall Stl. Thepull rod 68 extends downwardly through an opening in the plate Sil andthrough an opening in the toggle member 36 to extend below the memberwhere the pull rod is provided with the lateral projection 70. When thetoggle member 36 is located in its below dead center position as shownin FiGURE 7, it has been stated that the pressure fluid on the diaphragm16 will be below a predetermined limit. This down position of the togglemember 36 will, however, pull the rod 68 downwardly, thus locating thecontact strip 66 adjacent the bottom of the cavity 65 so that the stripis out of contact with the conductors 61 and 62. This structureaccordingly comprises the normally open contacts of the switch.

As the pressure conditions of the luid acting on the diaphragm 16 mayvary, it will be understood that the pivots 21 will have bodily movementto eect oscillating movement of the lever 22. When the pressure is belowa preset limit, lever 22 will engage its stop 31 which limits itsmovement in a downward direction under tension of the coil spring 32..ln this position of lever 22 the toggle member 36 will be located in abelow dead center position as a result of the action thereon by the overcenter spring 41. This position of the parts is shown in FEGURE 7 and itwill be observed that push rod 66 is so positioned as to allow thenormally closed contacts including the strip S6 and the conductors S1and 52 to close. However, the normally open contacts including the strip66 and the conductors 61 and 62 are open, since in this down position ofthe toggle member, the pull rod 63 has been pulled down locating strip66 in the bottom portion of the cavity 65 and out of engagement with thecontacts 61 and 62. ln the event the iluid acting on diaphragm 16 shouldincrease in pressure, then the toggle lever 22 will be caused to pivotin a counterclocltwise direction about its xed axis 36. Should thispivotal movement of lever 22- exceed a pre-set maximum, the said leverwill so influence the center spring l1 as to cause a snap actingmovement of the toggle member 36 into an above dead center position,such as shown in FIGURE 8. This snap-acting movement of the togglemember which takes place in a clockwise direction about its fixed axis37 will reverse the position of the contact strips. ln other words,contact strip 56 will be caused to move out of engagement with theconductors 51 and 52, whereas contact strip 66 will move into contactwith conductors 61 and 62. As the pressure of the fluid acting on thediaphragm 16 may vary above and below a predetermined maximum, thetoggle member 36 will have snap acting movement in opposite directionsbetween given extreme positions to thereby eilect the desired operationof the contact structure of the switch.

The invention is not to be limited to or by details of construction ofthe particular embodiment thereof illustrated by the drawings, asvarious other forms of the device will, of course, be apparent to thoseskilled in the art without departing from the spirit of the invention orthe scope of the claims.

What is claimed is:

l. In an electric switch, the combination with a supporting basestructure, of a frame assembly secured to said base structure andproviding a pair of spaced, upstanding side frames, toggle mechanismpivotally supported by the side frames, said mechanism including atoggle member having pivotal movement in a direction arallel to the sideframes, a contact block. of insulating material xedly supported by theside frames, a plurality of iixed contacts located within the contactblock, a plu- Irality of movable contacts within the said block forrespectively coacting with the fixed. contacts, a push rod operativelyconnecting the toggle member with certain of the movable contacts, and apull rod operatively connecting the toggle member with the remaining ofthe movable contacts.

2. In an electric switch, the combination with a supporting ringstructure, of a frame assembly secured to said ring structure andproviding a pair of spaced, upstanding side trames, a toggle leverpivotally supported -by the upstanding side frames, and adapted tooscillate in a direction parallel to the side frames, a toggle memberalso pivotally supported by the upstanding side frames so as tooscillate in a direction parallel to the side trames, resilient meansoperatively connecting the toggle member with the toggle lever wherebysaid member will move to and from positions on respective sides of deadcenter when the toggle lever is oscillated to a predetermined degree, acontact block of insulating material fixedly supported by the sideframes, a plurality of fixed contacts located within the block, aplurality of movable contacts. within said block for respectivelycoacting with the fixed contacts when the same are actuated, and meansfor actuating said movable contacts including .a push rod operativelyconnecting the toggle member with certain of the movable contacts and apull rod operatively connecting the toggle member with the remainingmovable contacts.

3. In an electric switch, the combination with a supporting ringstructure, of a frame assembly secured to said ring structure andproviding a pair of spaced, upstanding side frames, a toggleleverpivotally engaging the side frames at one edge thereof, said toggielever being disposed exteriorly of the side frames and being adapted tooscillate in a direction parallel to the side frames, a toggle memberpivotally engaging the side frames at the opposite edge thereof and alsobeing adapted to oscillate in a direction parallel to the side frames,resilient means disposed between the toggle lever and member andconnecting therewith whereby the toggle member has movement in oppositedirections between given extreme posi tions when the toggle lever isoscillated to a predetermined degree, a contact block of insulatingmaterial fixedly supported by the side frames, a plurality of fixedcontacts located within the block and which are disposed in pairs, amovable contact strip mounted within the lblock for coaction with afirst pair of said fixed contacts, another movable contact strip mountedwithin the block for coaction with a second pair of said fixed contacts,and means for actuating the said movable contact strips including a pushrod operatively connecting the toggle member with one of the movablecontact strips and a pull rod operatively connecting the toggle memberwith the other movable contact strip.

4. In an electric switch, the combination with a supporting ringstructure, of a frame assembly secured to said ring structure andproviding a pair of spaced, up standing side frames, a toggle leversupported by the side frames and movable about a fixed axis in adirection parallel to the side frames, a toggle member also supported bythe side frames and movable about a xed axis in a direction parallel tothe side frames, an overcenter spring between the toggle lever andmember whereby said toggle member has snap acting movement in oppositedirections between given extreme positions vwhen the toggle lever isoscillated to a predetermined degree, a contact block of insulatingmaterial ixedly supported by the side frames, a plurality of ixedcontacts located within the block and which are disposed in pairs, amovable contact strip for coaction with a first pair of said fixedcontacts, a push rod supporting said contact strip and operativelyconnecting with the toggle member, a second movable contact strip forcoaction with a second pair of said fixed contacts, and a pull rodsupporting said second contact strip and operatively connecting with thetoggle member.

5. An electric switch as dened by claim 4, additionally including coilsprings having encircling relation with the push rods respectively foryieldingly biasing the movable Contact strip supported by the particularrod into contact relation with its pair of lixed contacts.

6. ln a switch of the type as disclosed, a contact block having a pairof cavities therein at respective sides of the block, a pair ofconductors for each cavity, said conductors extending from the exteriorof the block to within the cavities respectively and said conductorsterminating therein, a contact strip within each cavity, resilient meansassociated with each contact strip and operative to main tain itscontact strip in contact with the terminal ends of the conductors withinits particular cavity, a push rod mounting one of said contacts stripsand having a portion engaging the strip to effect movement of the stripout of contact with the terminal ends of its conductors when the pushrod is actuated, and a pull rod mounting the other contact strip andhaving a portion engaging the strip to eiiect movement of the strip outof contact with the terminal ends of its conductors when the pull rod isactuated.

7. In a switch of the type as disclosed, a contact block having firstand second cavities therein at respective sides of the block, a pair ofconductors for each cavity, said conductors extending from the exteriorof the block to within the cavities respectively and said conductorsterminating therein, the terminating conductors within the first cavityhaving location adjacent the bottom wall of said cavity and theterminating conductors within the second cavity having location adjacentthe top wall of said cavity, a contact strip within each cavity,resilient means associated with each contact strip and operative tomaintain its contact strip in contact with the terminal ends of theconductors within its particular cavity, a push rod mounting the contactstrip in the first cavity and having a portion below the strip forengaging the same to eiect movement of the strip out of contact with theterminal ends of its conductors when the push rod is actuated, and apull rod mounting the contact strip in the second cavity and having aportion above the strip for engaging the same to effect movement of thestrip out of contact with the terminal ends of its conductors when thepull rod is actuated.

References Cited in the tile of this patent UNITED STATES PATENTS2,020,485 Van Valkenburg et al. Nov. 12, 1935 2,193,127 Furnas et alMar. 12, 1940 2,281,544 Beeman et al. May 5, 1942 2,307,265 Hansen Jan.5, 1943 2,412,095 Muerle Dec. 3, 1946 2,574,770 Zeller Nov. 13, 19512,623,963 Wolfe et al Dec. 30, 1952

